CONTAGIOUS DISEASES OF DOMESTICATED ANIMALS. 77 



Decatur County aud all of Harden. In Henderson County it reaches 

 as far north as Shady Hill, then passes directly west to the vicinity of 

 Mifflin, in the same county. From here the direction is slightly south 

 of west to Denmark, the boundary between Madison being- crossed 2 

 miles north of Hardeman County; from here the direction is westerly 

 to Stanton Depot, in Haywood County, and onward toward the south- 

 western corner of Haywood and along the northern boundary of Shelby 

 to the Mississippi Itiver. All of Shelby and Fayette Counties appear 

 to be infected, while Tipton, as far as we have been able to learn, is free 

 from any infection. 



This concludes our examination of the district permanently infected 

 with southern cattle fever for the year. It will be seen that a consider- 

 able portion of Tennessee has already become infected. Even the mount- 

 ainous counties in the southeastern part of the State have been in- 

 vaded, while in the river valleys ofthecentra.1 part of the State the line 

 has reached considerably farther toward the north. Along the whole 

 line of the infected district in this State, as in the other States previ- 

 ously examined, we have found the same history of the extension of 

 of the permanently-infected district. At some points this extension 

 has been insignificant or is scarcely noticeable within the last quar. 

 ter of a century, but in the situations more favorable to the progress 

 of the disease there has apparently been a regular advance of from one 

 to four miles per year. This history coincides substantially with what 

 was learned of the progress of the disease in Virginia, Xorth Carolina, 

 and Georgia. As a consequence of these facts there can be no longer 

 substantial reason to doubt the continued extension toward the north 

 of the district permanently infected with this disease. Considering the 

 extreme temi^erature which occurs in the mountains of southeastern 

 Tennessee and in the part of this State located in the Mississippi Valley, 

 we can scarcely hope that the winters in any considerable part of the 

 stock-raising section of the country will be sufficiently severe to i)rove 

 a permanent check to the extension of this contagion. 



It is proposed to continue the examination of this district across Arkan- 

 sas, Indian Territory, aud Texas, to the Rio Grande 111 ver, and it is believed 

 that a definite location of this line will be of great assistance to those en- 

 gaged in the live-stock industry in the whole southwestern part of the coun- 

 try. The mortality among thoroughbred cattle taken south of the border 

 line of the permanently infected district is so great that it has become a 

 matter of importance to buy animals which have acquired a certain 

 amount of immunity from this disease. It is believed by many breed- 

 ers that by establishing breeding farms Just within the line of infection 

 that there will be a smaller mortality from the disease, and that the 

 animals raised under these conditions will still be able to resist its ef- 

 fects in a very perfect manner. Already such farms have been estab- 

 lished in Southeast Kansas and Southern Missouri, under the belief that 

 animals raised in this lo<^ality will prove insusceptible to the disease 



